1 вариант
1)х+(8-3х)=12
х+8-3х=12
-2х=4
х=-2
2)а)4х+1=-3х+15
7х=14
х=2
б)4х+2(1-3х)=13
4х+2-6х=13
-2х=11
х=-5,5
3)1/2х-1=1/3(х+3/4)
1/2х-1=1/3х+1/4
х(1/2-1/3)=1 1/4
1/6х=5/4
х=5/4:(1/6)=5/4*(6)=30/4=7,5
2 вариант
1)х+(7-2х)=10
х+7-2х=10
-х=3
х=-3
2)а)3х+5=-4х+19
7х=14
х=2
б)х+3(1-2х)=23
х+3-6х=23
-5х=20
х=-4
3)1/3х-1=1/4(х+4/5)
1/3х-1=1/4х+1/5
х(1/3-1/4)=1 1/5
1/12х=6/5
х=6/5:(1/12)=6/5*(12)=72/5=14 2/5=14,4
3 вариант
1)2х + (11-4х) = 21
2х + 11 - 4х =21
-2х = 10
х=-5
2)а)7х+13=-5х+25
12х = 12
х=1
б) х+5(2-4х)=29
х+10-20х=29
-19х=19
х=-1
3)1/2х +1=-1/3(х+3/4)
1/2х+1=-1/3х - 1/4
х(1/2+1/3)=-1 1/4
5/6х=-5/4
х=(-5/4):(5/6)=(-5/4)*(6/5)=-6/4=-1,5
4 вариант
1) 3х+ (13-8х)=33
3х+13-8х=33
-5х=20
х=-4
2)а)6х+12=-7х+25
13х=13
х=1
б)х+6(3-3х)=35
х+18-18х=35
-17х=17
х=-1
3) 1/3х +1 =-1/4(х+4/5)
1/3х+1=-1/4х-1/5
х(1/3+1/4)=-1 1/5
7/12х=-6/5
х=(-6/5):(7/12)=(-6/5)*(12/7)=-72/35=-2 2/35